Abstract TP47: Intracranial Intraplaque Hemorrhage in Acute Stroke: Interim Results of the Stroke Imaging Package Study

Introdution: Intracranial artery atherosclerosis is an important cause of ischemic stroke, especially in people of Asian origin. Intraplaque hemorrhage is supposed to be a predictor of ischemic event. The goal of this study was to examine the occurrence of intraplaque hemorrhage in a large cohort of Chinese patients with acute ischemic stroke. Methods: Patients with first ever stroke within 72 hours from onset, confirmed by diffusion weighted imaging, were recruited from 16 medical centers. Conventional MRI, magnetic resonance angiography, HRMRI (including 3-dimentional T1 images and 2-dimentional T2 images), and SWI were performed. Intraplaque hemorrhage was identified if hyperintense signals on 3-dimentional T1 images of HRMRI were observed within intracranial plaques. Results: Six hundred and one patients (70% male, mean age 61±16 years old, mean NIHSS 6± 5) were enrolled. Median time from symptom onset to MRI was 44 ± 20 hours. Of them, 240(40%) were diagnosed with large artery atherosclerosis (LAA) stroke. Intracranial intraplaque hemorrhage was identified in 15 intracranial plaques of 13 patients with LAA stroke. Six plaques with intraplaque hemorrhage were asymptomatic and irrelevant to ischemic infarct lesions. In 2 patients, both symptomatic and asymptomatic intraplaque hemorrhage were observed. Conclusions: The prevalence of intracranial intraplaque hemorrhage was low (5.4%)in acute stroke patients. The clinical importance of asymptomatic intraplaque hemorrhage need further investigations.